﻿1 00:00:00,133 --> 00:00:01,000 [Music] 2 00:00:01,000 --> 00:00:04,500 I’m Ernie Wright. I work in the Scientific Visualization Studio 3 00:00:04,500 --> 00:00:06,900 at NASA’s Goddard Space Flight Center. 4 00:00:06,900 --> 00:00:08,700 We’re looking at a computer model 5 00:00:08,700 --> 00:00:11,233 of the view at the South Pole of the Moon. 6 00:00:11,233 --> 00:00:13,233 This is like a time-lapse to show the motion 7 00:00:13,233 --> 00:00:17,466 of the Sun and the Earth and how the shadows change over time. 8 00:00:17,466 --> 00:00:20,400 Things don’t rise and set in the usual way here. 9 00:00:20,400 --> 00:00:23,600 The sun travels around the horizon, never getting more 10 00:00:23,600 --> 00:00:26,033 than a degree and a half above or below it, 11 00:00:26,033 --> 00:00:28,933 so there are always these long shadows. 12 00:00:28,933 --> 00:00:31,566 And from here, the Earth appears to be upside-down 13 00:00:31,566 --> 00:00:36,733 and rotating backwards, but that’s just because of our point of view. 14 00:00:36,733 --> 00:00:39,200 The Earth doesn’t move much in the Moon’s sky. 15 00:00:39,200 --> 00:00:43,233 It’s always in roughly the same place, just sort of bobbing around. 16 00:00:43,233 --> 00:00:45,233 That’s true everywhere on the near side of the Moon. 17 00:00:45,233 --> 00:00:47,200 It’s a consequence of the Moon always pointing 18 00:00:47,200 --> 00:00:49,800 the same face toward Earth. 19 00:00:49,800 --> 00:00:51,666 It takes about a month for the Sun 20 00:00:51,666 --> 00:00:53,933 to make a complete circuit around the horizon, 21 00:00:53,933 --> 00:00:59,233 and every so often, it’ll pass behind the Earth, creating an eclipse. 22 00:00:59,233 --> 00:01:03,266 I’ve slowed down time here a little so that it’s easier to see. 23 00:01:03,266 --> 00:01:06,066 On Earth, that would be a total lunar eclipse - 24 00:01:06,066 --> 00:01:09,400 the Moon passing through the shadow cast by the Earth. 25 00:01:09,400 --> 00:01:14,000 But if you’re standing on the Moon, it’s an eclipse of the Sun. 26 00:01:14,000 --> 00:01:16,700 The terrain at the South Pole is especially rugged. 27 00:01:16,700 --> 00:01:19,533 The rim of Shackleton crater is in the foreground here, 28 00:01:19,533 --> 00:01:22,766 and the mountain off on the horizon is unofficially known as 29 00:01:22,766 --> 00:01:26,700 Mons Malapert - it's about 85 miles away. 30 00:01:26,700 --> 00:01:29,166 Shackleton crater is about 13 miles wide, 31 00:01:29,166 --> 00:01:33,333 not quite as wide as the Grand Canyon, but it’s twice as deep. 32 00:01:33,333 --> 00:01:36,600 Sunlight never reaches the crater floor, so temperatures there 33 00:01:36,600 --> 00:01:41,466 are around 300 degrees below zero Fahrenheit. 34 00:01:41,466 --> 00:01:43,366 This model of the terrain is made possible 35 00:01:43,366 --> 00:01:46,233 by Lunar Reconnaissance Orbiter, which has been mapping 36 00:01:46,233 --> 00:01:50,566 the surface of the Moon from lunar orbit since 2009. 37 00:01:50,566 --> 00:01:53,700 LRO’s maps will be incredibly important for exploring the Moon 38 00:01:53,700 --> 00:01:56,866 and locating water and other resources there. 39 00:01:56,866 --> 00:01:58,900 [Music fades]